Résumé
Licorice extract has the efficacy of anti-inflammatory, anti-viral, anti-oxidation and anti-aging. It is widely used in the pharmaceutical, food and cosmetic industries. This paper analyzes the status of licorice extract’s global trade and its international competitiveness. The main purpose is to clarify the status of our country’s licorice extract in the international market and provide reference for improving the international competitive advantage of licorice extract of China. Germany, the United States, Netherlands, France, Japan, Israel and China were the main import and export countries for licorice extract. The international market share (IMS), trade competitiveness index (TC Index), revealed comparative advantage index (RCA Index) and competitive advantage index (CA Index) were used to compare the licorice extract’s international competitiveness of these countries. It showed that Israel has the strongest international competitiveness and followed by France. The United States has the maximum IMS, but its competitiveness was on sagging tendency. Germany and the Netherlands are the major importers of licorice extract. Although they are lack of international competitiveness, its international competitiveness is on the rise, especially in Germany. China’s licorice extract has a high IMS, but its international trade competitiveness is weak, far lower than the United States and France. Japan was the basic export country of China’s licorice extract. The TC index and CA index of licorice extract in Japan are less than zero, which means Japan’s licorice extract is not competitive.
Résumé
Objective To establish a method for the simultaneous determination of liquiritin, isoliquiritin, glycyrrhizin, isoliquiritigenin and glycyrrhizic acid in licorice extract. Methods Liquiritin, isoliquiritin, glycyrrhizin, isoliquiritigenin and glycyrrhizic acid in licorice extract were determined by HPLC dual wavelength spectrophotometry. Symmetry C18 column (4.6 mm × 250 mm, 5 μm) was used. The mobile phase was acetonitrile (A) - 0.085％ phosphoric acid water (B), ingradient elution mode (0–8 min, 81％ B; 8–35 min, 81％→50％ B; 35–60 min, 50％ B) with the flow rate of 1.0 mL/min. The sample size was 10 μL, and column temperature was room temperature. Dual wavelength detection, λ1=237 nm, λ2=254 nm. Results Liquiritin, isoliquiritin, glycyrrhizin, isoliquiritigenin and glycyrrhizic acid were linear in the ranges of 0.0408–0.816 μg, 0.0528–1.056 μg, 0.0224–0.448 μg, 0.0212–0.424 μg, and 0.0448–0.896 μg, respectively. The average recovery was 98.69％, 98.31％, 99.10％, 98.55％, and 99.14％, respectively; RSD was 1.39％, 1.29％, 1.78％, 2.14％, and 1.15 ％, respectively. Conclusion The method is accurate, reliable and specific. The results are stable with good repeatability. It can be used for the determine of above 5 components in licorice extract.
Résumé
Objective: Study on the influence of ζ potential on flocculating rate of Chinese herbs water-extract liquid. Methods: Chitosan of natural macromolecule flocculant was adopted to remove the flocculation impurity of the herb licorice (Glycyrrhizae Radix) extract, and the deep connection between ζ potential and liquid flocculating rate was proved by single factor experiment, orthogonal experiment, and granularity. Results: Under the influence of single factor conditions, absolute value of ζ potential of the system is lower, while the flocculation rate is higher. Based on orthogonal experiment, the optimum process condition of flocculating licorice extract is determined to be the flocculant dosage quantity of 0.347 g/L, pH value of 6, temperature of 30℃, and the system ζ potential of -1.67 mV, which is close to the isoelectric point among all the experiment. Whereas the flocculating rate was as high as 95.29%. The ζ potential of solution before flocculation is -14.78 mV, the average particle size is 17.12 μm; After the flocculation the ζ potential of clear liquid is -1.67 mV, the average particle size is 6.77 μm. The change of ζ potential affected the particle behavior of sol system and ultimately affected the liquid flocculating rate. Conclusion: In the process of flocculating herb licorice extract, the ζ potential has the important influence on the flocculation of herb extract. Absolute value of ζ potential of the system is lower, closer to the isoelectric point, the flocculation rate is higher. The ζ potential that reflects the flocculation essence provides a strong justification for the selection of flocculation conditions.